The new machine comes in four basic configurations: two 21.5-inch models with a 2.5GHz Quad-Core Intel Core i5 and 2.7GHz Quad-Core Intel Core i5 processor respectively, and two 27-inch models with a 2.7GHz Quad-Core Intel Core i5 and 3.1GHz Quad-Core Intel i5. Apple is also offering built-to-order Web-only options to bump the 21.5-inch model to a 2.8GHz quad-core Intel Core i7, and the 27-inch model to a 3.4GHz Intel Core i7.

The low-end 21.5-inch model sports a 500GB hard drive and an AMD Radeon HD 6750M with 512MB of video RAM, while the more powerful 21.5-inch configuration has a 1TB hard drive and an AMD Radeon HD 6770M with 512MB of video RAM. Both versions feature a 1920 by 1080 pixel display and 4GB of memory. They retail for $1,199 and $1,499 respectively.

Both of the 27-inch models sport a 1TB hard drive, 4GB of RAM, and a 2560 by 1440 pixel display. The 2.7GHz model has an AMD Radeon HD 6770M with 512MB of video RAM, while the 3.1GHz model has an AMD Radeon HD 6970M with 1GB of video RAM. They cost $1,699 and $1,999 respectively.

The i7 processor upgrades add $200 to the cost.

Apple first unveiled Thunderbolt with its new MacBook Pro line released in February. Co-developed with Intel, Thunderbolt offers two bi-directional channels that can transfer data at up to 10Gbps each—12 times faster than the theoretical maximum of FireWire 800. The technology is based on the PCI Express protocol that most Macs use for internal I/O, but via adapters it can support pretty much any other type of connectivity protocol, including FireWire, USB, and Gigabit Ethernet. The smaller iMac sports a single Thunderbolt port; the larger version includes two.

That February MacBook Pro refresh also marked the first time Apple released FaceTime HD cameras, which now come to the iMac as well. Mac to Mac FaceTime calls support up to 720p resolution; calls to iOS devices won't support full high definition.

Apple says the new iMac is up to 70 percent faster than its predecessor, with graphics performance that's up three times as fast. Customers can choose between a Magic Mouse or a Magic Trackpad with their order.

The new iMac also meets the Energy Star 5.2 requirements and achieves EPAT Gold rating, according to Apple. The computer is built with components that are free of mercury, arsenic, PVC, and brominated flame retardants.

This story, "Apple releases Thunderbolt-equipped iMac line" was originally published by
Macworld.